Expose unsupported MP4/MOV edit-list features through the API

Mediabunny logs warnings when an MP4/MOV edit list (elst box) contains unsupported instructions, such as multiple media edits or a media_rate other than 1.

https://github.com/Vanilagy/mediabunny/blob/cee57d1cdfd1776d515c081057b50eb337291e32/src/isobmff/isobmff-demuxer.ts#L956-L971

We would like to detect these cases and fall back to HTML video playback, since decoding can succeed while these instructions are ignored.

Logs aren't the right interface for this. Applications should be able to query unsupported features for an input or track directly, without matching warning messages.

Would you consider exposing this information through the API? This would preserve the current best-effort behavior while letting consumers decide when to use a fallback.

Happy to contribute if this sounds useful.